ABSTRACT
Objectives: Increasing activity levels in older people is important for maintaining quality of life and ameliorating the risks of morbidity related to falls, depression, and dementia. This study aimed to clarify the seasonal variation effects on total energy expenditure, number of steps, time spent in low- and moderate- or high-intensity physical activities, and daily activities performed.Patients and Methods: This was a cross-sectional study of 22 community-dwelling older individuals (3 men, 19 women; mean age, 75.1 ± 7.3 years) living in three districts of Gero, Gifu, who participated in the Gero Salon Project hosted by the Social Welfare Councils. Evaluations were conducted in each season from September 2016 to August 2017. We used a uniaxial accelerometer, the Lifecorder device, which measures physical activity, and the Physical Activity Scale for the Elderly to evaluate activities of daily living. Data were analyzed using the multiple comparisons (Bonferroni correction) method.Results: Total energy expenditure and time spent in moderate- or high-intensity activities did not show seasonal variations. However, the lowest number of steps was taken during the winter, and the number of steps increased significantly from winter to spring. The time spent in low-intensity physical activities was significantly longer in the spring and summer than in the winter. There was no significant seasonal difference in total Physical Activity Scale for the Elderly score, leisure activities, domestic activities, or work-related activities. However, there was a significant difference between the summer and winter scores in “outdoor gardening,” with the lowest score observed during the winter.Conclusions: With climate changes in the winter months, “outdoor gardening” becomes difficult, thus decreasing the number of steps taken. Therefore, it is necessary to identify other ways for older people to maintain physical activity during the winter season.
ABSTRACT
<i>Centrocestus armatus</i> is an intestinal parasite belonging to the family Heterophyidae. We developed an apparatus for recovering cercariae and clarified the infection dynamics of this parasite. To clarify the circadian rhythm of cercarial shedding in the summer season, we filtrated 30 l of river water every 2 h for 24 h. Cercariae were first detected between 06:00 and 08:00 h, increased over time to reach peak at 16:00 h and decreased thereafter, thus showing a single-peak pattern. In a survey of seasonal change, approximately 200 cercariae were contained in 1 l of river water during the summer season, while none were found during the winter. This cercarial shedding pattern appeared to be related to sunrise/sunset and water/atmosphere temperature. Therefore, we examined whether cercarial shedding was affected by light or temperature changes under laboratory conditions, and confirmed that both light and temperature were important factors for cercarial shedding. Light was a stronger factor than water temperature. Cercarial shedding of <i>C.</i> <i>armatus</i> occurred in response to temperature and light. The change in the number of juvenile metacercariae detected in fish brain corresponded with monthly detection rates of cercariae; however, the incidence of new infections decreased in August. This suggests that <i>Nipponocypris temminkii</i> contains a defense mechanism against new infections that may have hindered the increase in parasite infectivity. These results clarified the smooth infection from the first to the second intermediate host of <i>C. armatus</i> in the endemic river. Throughout the study period, fecal samples were collected from 19 kites, 114 herons, and three unidentified species. However, our results using <i>C. armatus</i> showed a low value of 1% in herons and 5% in kites. The infection dynamics of final host to first intermediate host need to be further investigated.
ABSTRACT
The prevalence of <I>Centrocestus armatus</I> metacercariae in fresh water fishes were examined in Hyogo Prefecture, western Japan for a period of one year from April 2003 to March 2004. Three species of cyprinoid fish, namely <I>Zacco temminckii, Zacco platypus,</I> and <I>Pseudogobio esocinus,</I> were found to harbor metacercariae of <I>C. armatus.</I> The infection rate of metacercariae in <I>Zacco temminckii, Zacco platypus,</I> and <I>Pseudogobio esocinus</I> was 99% (371⁄377), 100% (8⁄8), and 100% (2⁄2), respectively. The mean number of metacercariae recovered was 232 for <I>Z. temminckii,</I> 2,123 for <I>Z. platypus,</I> and 20 for <I>P. esocinus.</I> However, we focused on <I>Z. temminckii</I> in this study because it was found to be the most predominant fish species in the Chikusa River and to have high a metacercariae prevalence as well. <I>In Z. temminckii,</I> metacercariae were distributed in the brain (37%), viscera (35%), muscles (29%) and gills (0%). No metacercariae were recovered from the scales and fins. This is the first report of the occurrence of <I>C. armatus</I> metacercariae in the brain region of the second intermediate fish. The prevalence of <I>C. armatus</I> metacercariae was almost constant throughout the year, and no positive correlation was found between the prevalence and seasonal changes. However, a positive relationship was observed between prevalence of metacercariae and fish length, I.e., the intensity of infection increases with the size of the fish host (p < 0.05). People in the survey area sometimes eat fish raw, indicating enlightenment as well as the countermeasures to prevent <I>C. armatus</I> infection is needed.